Free-Radical Ring Closure to Conformationally Locked α-<scp>l</scp>-Carba-LNAs and Synthesis of Their Oligos: Nuclease Stability, Target RNA Specificity, and Elicitation of RNase H
作者:Qing Li、Fengfeng Yuan、Chuanzheng Zhou、Oleksandr Plashkevych、Jyoti Chattopadhyaya
DOI:10.1021/jo100900v
日期:2010.9.17
A new class of conformationally constrained nucleosides, α-l-ribo-carbocyclic LNA thymidine (α-l-carba-LNA-T, LNA is an abbreviation of locked nucleic acid) analogues and a novel “double-locked” α-l-ribo-configured tetracyclic thymidine (6,7′-methylene-bridged-α-l-carba-LNA-T) in which both the sugar puckering and glycosidic torsion are simultaneously constrained, have been synthesized through a key
一类新的构象受限的核苷,α-的升-核糖-碳环LNA胸苷(α-升-carba-LNA-T,LNA是锁核酸的缩写)类似物和一种新颖的“双锁定”α-升-核糖结构的四环胸苷(6,7'-亚甲基-桥联的-α- 1-碳-LNA-T),其中糖的起皱和糖苷的扭曲同时受到限制,这是通过涉及5- exo游离的关键步骤合成的-自由基分子内环化。这些α- l-carba-LNA类似物随后已转化为相应的亚磷酰胺,并掺入了等序反义寡核苷酸(AONs)中,然后对它们的双链体进行了热变性,核酸酶稳定性和RNase H募集能力进行了研究。与天然异源双链体相比,在AON / RNA异源双链体的AON链中引入单个6',7'-取代的α- 1 -carba-LNA-T修饰导致T m降低2-3°C,而已发现在AON链中相同位置的亲本2'-oxa-α- 1 -LNA-T修饰导致T m增加3-5°C。这表明6'和7'取代导致修饰的异源双链体的热稳定性大大降低,尤其是位于α